/** create by liuhua at 2019年5月21日 下午2:48:53**/
package com.star.truffle.gateway.config;

import java.util.Collections;
import java.util.List;

import org.springframework.beans.factory.ObjectProvider;
import org.springframework.boot.autoconfigure.web.ResourceProperties;
import org.springframework.boot.autoconfigure.web.ServerProperties;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.boot.web.reactive.error.ErrorAttributes;
import org.springframework.boot.web.reactive.error.ErrorWebExceptionHandler;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.Ordered;
import org.springframework.core.annotation.Order;
import org.springframework.http.codec.ServerCodecConfigurer;
import org.springframework.web.reactive.result.view.ViewResolver;

import com.star.truffle.gateway.exception.JsonExceptionHandler;

/**
 * 覆盖默认的异常处理
 * 
 */
@Configuration
@EnableConfigurationProperties({ ServerProperties.class, ResourceProperties.class })
public class ErrorHandlerConfiguration {

  private final ServerProperties serverProperties;

  private final ApplicationContext applicationContext;

  private final ResourceProperties resourceProperties;

  private final List<ViewResolver> viewResolvers;

  private final ServerCodecConfigurer serverCodecConfigurer;

  public ErrorHandlerConfiguration(ServerProperties serverProperties, ResourceProperties resourceProperties,
      ObjectProvider<List<ViewResolver>> viewResolversProvider, ServerCodecConfigurer serverCodecConfigurer,
      ApplicationContext applicationContext) {
    this.serverProperties = serverProperties;
    this.applicationContext = applicationContext;
    this.resourceProperties = resourceProperties;
    this.viewResolvers = viewResolversProvider.getIfAvailable(Collections::emptyList);
    this.serverCodecConfigurer = serverCodecConfigurer;
  }

  @Bean
  @Order(Ordered.HIGHEST_PRECEDENCE)
  public ErrorWebExceptionHandler errorWebExceptionHandler(ErrorAttributes errorAttributes) {
    JsonExceptionHandler exceptionHandler = new JsonExceptionHandler(errorAttributes, this.resourceProperties,
        this.serverProperties.getError(), this.applicationContext);
    exceptionHandler.setViewResolvers(this.viewResolvers);
    exceptionHandler.setMessageWriters(this.serverCodecConfigurer.getWriters());
    exceptionHandler.setMessageReaders(this.serverCodecConfigurer.getReaders());
    return exceptionHandler;
  }

}
